›› WHAT IS CERVICOGENIC HEADACHE?

Cervicogenic Headache is a relatively new medical term and it refers to headaches, which originate from tissues and structures in the cervical spine or neck region. It has been quiet a few years since recognition but the exact mechanism of cervicogenic headache is still unclear. Perhaps quotations of several specialists in this area will give you better idea of a nature and symptoms of the condition.

Excerpts:

Daniel J. Hurley, M.D.
Whether from chronic tension or acute whiplash injury, intervertebral disc disease or progressive facet joint arthritis, the neck can be a hidden and severely debilitating source of headaches. Such headaches are grouped under the term “cervicogenic headache”, indicating that the primary contributing structural source of the headache is the cervical spine. There are well mapped out patterns of headache relating to a multiplicity of muscular trigger points in the neck and shoulder-blade (or peri-scapular) region, as well as to disc and joint levels in the upper cervical spine. Even headaches located predominantly in the forehead, or behind, in and around the eyes are very often “referred” pain zones for pathology located in the back of the neck and at the base of the skull. This base of the skull area is called the suboccipital region, because it is below the occipital part of the head. The joints connecting the top two or three levels of the cervical spine to the base of the skull handle almost 50% of the total motion of the entire neck and head region, thus absorbing a continuous amount of repetitive stress and strain, in addition to bearing the primary load of the weight of the head. Fatigue, postural malalignment, injuries, disc problems, joint degeneration, muscular stress and even prior neck surgeries all can compound the wear and tear on this critical region of the human skeletal anatomy. One may also develop a narrowing of the spinal canal itself, through which runs the spinal cord and all of its exiting nerve roots, leading to a condition termed spinal stenosis, also a possible source of headaches, among other symptoms.

Mary Jo Curran, MD
At this point we can’t point to the exact (even smallest) c-Spine abnormality as a definite source of cervicogenic headache. Ascending fibers from the C1 and C2 nerve roots are intimately involved with the trigeminal nucleus at the level of the brainstem. The nociceptive afferents from the trigeminal nerve and the receptive fields from the first three cervical nerves converge in the trigeminocervical nucleus. The structures innervated by C1-3 are capable of causing headache. These structures include muscles, joints, a portion of dura, ligaments, and the vertebral arteries.

Lower segmental levels and the cervical facet joints C2-3 and C4-5, have also been described as contributing to cervicogenic headache. There is a case report of a C6-7 disc herniation as the cause of a 15-year unilateral headache. The patient developed a C7 radiculitis and a C6-7 disc decompression alleviated the long-standing headache. The C2 and C3 nerve roots may also be the source of headache. The C2 ganglion may be injured by whiplash.

Differentiating between cervicogenic headache and other forms of headache is difficult because there may be variability in presentation and also considerable symptom overlap. Diagnostic injections have a role in not only differentiating different types of headaches, but also identifying the pain generator. Diagnostic injections of the cervical facet joints (or medial branch blocks), blocks of the cervical nerves, cervical discography, sphenopalatine and sympathetic blocks often times will elucidate the etiology of pain.

Since there are no consistent findings on physical exam, many authors recommend diagnostic C2 root and ganglion blocks should be considered to differentiate cervicogenic headache from migraine, chronic paroxysm hemicrania, hemicrania continua and tension-type headaches.